Added first draft of login and tour select page

lib/model/address.dart

@@ -0,0 +1,15 @@
+class Address {
+  String street;
+  String housingNumber;
+  String postalCode;
+  String city;
+  String country;
+
+  Address({
+    required this.street,
+    required this.housingNumber,
+    required this.postalCode,
+    required this.city,
+    required this.country,
+  });
+}